BUILDING TRANSITIONS USING INTEL IMAGE LIBRARY
PURPOSE:
- To do some programming involving image processing.
- To create transitions that can be used to creates a more complex video editing software.
DISCUSSION
We want to create transitions between two still images. In order to make a moving transition between one image to the next image, we need to make different images every different time. To create different transitions, we need to calculate the coordinates of the new image for different t, and use different function helper in Intel Image library in order to create the effect we want.
We will have two source image, called 'a' and 'b', and a result image called 'r'. The transitions created will combine the effect created in the first image and the second image. We used factor time 't' which goes from 0 to 1. For every different time, we call the function transitions, which will create different effect, and store it in the image 'r'.
TOOLS
In order to make different effects, we use Intel Image Library as a helper. The Intel Image Library has a lot of useful functions that can be used to define and manipulating images.
Some useful terms in Intel Image library:
1. Coordinate System
The coordinate system is defined from left to right and top to bottom.
2. Define an image
Each structure called IplImage contains pointer to aligned image, pointer to ROI and mask ROI, IplImage size, and Image header versions, among other things.
3. ROI(Region Of Interest)
Region of Interest on an image is the portion of an image which we are interested in. Region of Interest of an image is defined as the whole image as a default, and can be changed by using the function IplROI(). We can change the coordinates of this ROI and manipulate it to create transitions.
4. IPLSet
This function is used to set the image. For example if we set the image to 0, it will give us black screen. This is particularly useful when we want to create transitions, but we don't want the previous effect shows up in. IplSet allows us to clear the screen before we goes on to the next step.
5. CopyFrom
This function copy from a source image to destination image.
6. IplWarpPerspective
IplWarpPerspective allows us to perform geometric transforms to stretch the image.
RESULTS
1. Vertical Transitions, Checker Wipe, Checker Board, and Center Split
CONCLUSION
Transitions can be created by changing coordinates the ROI of source image, combining them, and putting them to the result image. Functions that is defined inside Intel Image library can be used to create effets we want to the image. These transitions project can be used as a base to create a video editing software.